src/ceph/src/client/barrier.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  *
   5  * Copyright (C) 2012 CohortFS, LLC.
   6  *
   7  * This is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License version 2.1, as published by the Free Software
  10  * Foundation.  See file COPYING.
  11  *
  12  */
  13
  14 #ifndef BARRIER_H
  15 #define BARRIER_H
  16
  17 #include "include/types.h"
  18 #include <boost/intrusive/list.hpp>
  19 #define BOOST_ICL_USE_STATIC_BOUNDED_INTERVALS
  20 #include <boost/icl/interval_set.hpp>
  21 #include "common/Mutex.h"
  22 #include "common/Cond.h"
  23
  24 class Client;
  25
  26 typedef boost::icl::interval<uint64_t>::type barrier_interval;
  27
  28 using namespace std;
  29
  30 /*
  31  * we keep count of uncommitted writes on the inode, so that
  32  * ll_commit_blocks can do the right thing.
  33  *
  34  * This is just a hacked copy of Ceph's sync callback.
  35  */
  36
  37 enum CBlockSync_State
  38 {
  39   CBlockSync_State_None, /* initial state */
  40   CBlockSync_State_Unclaimed, /* outstanding write */
  41   CBlockSync_State_Committing, /* commit in progress */
  42   CBlockSync_State_Completed,
  43 };
  44
  45 class BarrierContext;
  46
  47 class C_Block_Sync;
  48
  49 typedef boost::intrusive::list< C_Block_Sync,
  50                                 boost::intrusive::member_hook<
  51                                   C_Block_Sync,
  52                                   boost::intrusive::list_member_hook<>,
  53                                   &C_Block_Sync::intervals_hook >
  54                                 > BlockSyncList;
  55
  56 class Barrier
  57 {
  58 private:
  59   Cond cond;
  60   boost::icl::interval_set<uint64_t> span;
  61   BlockSyncList write_list;
  62
  63 public:
  64   boost::intrusive::list_member_hook<> active_commits_hook;
  65
  66   Barrier();
  67   ~Barrier();
  68
  69   friend class BarrierContext;
  70 };
  71
  72 typedef boost::intrusive::list< Barrier,
  73                                 boost::intrusive::member_hook<
  74                                   Barrier,
  75                                   boost::intrusive::list_member_hook<>,
  76                                   &Barrier::active_commits_hook >
  77                                 > BarrierList;
  78
  79 class BarrierContext
  80 {
  81 private:
  82   Client *cl;
  83   uint64_t ino;
  84   Mutex lock;
  85
  86   // writes not claimed by a commit
  87   BlockSyncList outstanding_writes;
  88
  89   // commits in progress, with their claimed writes
  90   BarrierList active_commits;
  91
  92 public:
  93   BarrierContext(Client *c, uint64_t ino);
  94   void write_nobarrier(C_Block_Sync &cbs);
  95   void write_barrier(C_Block_Sync &cbs);
  96   void commit_barrier(barrier_interval &civ);
  97   void complete(C_Block_Sync &cbs);
  98   ~BarrierContext();
  99 };
 100
 101 #endif